Open Access

On the Superstability of the Pexider Type Trigonometric Functional Equation

Journal of Inequalities and Applications20102010:897123

Received: 23 October 2009

Accepted: 3 January 2010

Published: 21 January 2010


We will investigate the superstability of the (hyperbolic) trigonometric functional equation from the following functional equations: and , which can be considered the mixed functional equations of the sine function and cosine function, the hyperbolic sine function and hyperbolic cosine function, and the exponential functions, respectively.

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Authors’ Affiliations

Department of Mathematics, Kangnam University


© Gwang Hui Kim 2010

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